Generally, a hydrolysis of vinyl esters and a cleavage of vinyl ethers are conducted in the presence of an acid or basic catalyst. However, this method cannot be used when a functional group or a protective group which is sensitive to an acid or a base is present.
Thus, methods using enzymes or microorganisms other than chemical measures are known as mild methods (see, for example, Prior Art Reference 1).
There are also studies of artificial enzymes to reproduce enzymatic functions by an artificially synthesized molecule though these enzymes are still impractical to use (see, for example, Prior Art Reference 2).
However, in the methods using an enzyme reaction or a reaction using artificial enzyme, substrate concentration is usually about 0.1% to several % by weight. The reaction is therefore conducted in a considerably diluted solution, resulting in low reaction efficiency.
Moreover, in enzyme reactions or reactions using microorganisms, it is necessary for the pH of the solution to be adjusted by using a considerable amount of a buffer solution, and in many reactions, nutrient source is also required.
Examples using metal compounds are also known, i.e., a method in which propenyl ether is cleft in a mild condition by using a palladium compound and a copper compound to obtain alcohols. However, only a racemate can be obtained in this method (see, for example, Prior Art Reference 3).
The prior arts relating to the present invention are as follows, and the following documents are incorporated as reference in this specification.
1. Luzzio. F. A etc., Tetrahedron: Asymmetry, 2002, 1173-1180
2. Zhang. B.; J. Am. Chem. Soc., 1997, 119, 1676-1681
3. Mareyala, H. B. stc., Tetrahedron, Vol. 53, 17501-17512, 1997